JS 网页小特效

/* 鼠标特效 */
var a_idx = 0;
jQuery(document).ready(function($) {
    $("body").click(function(e) {
        var a = new Array("❤你❤","❤真❤","❤棒❤","❤你❤","❤怎❤","❤么❤","❤这❤","❤么❤","❤好❤","❤看❤");
        var $i = $("<span></span>").text(a[a_idx]);
        a_idx = (a_idx + 1) % a.length;
        var x = e.pageX,
        y = e.pageY;
        $i.css({
            "z-index": 9999,
            "top": y - 20,
            "left": x,
            "position": "absolute",
            "font-weight": "bold",
            "color": "rgb("+~~(255*Math.random())+","+~~(255*Math.random())+","+~~(255*Math.random())+")"
        });
        $("body").append($i);
        $i.animate({
            "top": y - 180,
            "opacity": 0
        }, 1500, function() {
            $i.remove();
        });
    });
});
// 修改网站标题
document.addEventListener("visibilitychange", function() {
    console.log(document.visibilityState);
    if(document.visibilityState == "hidden") {
        document.title = '人呢？去哪了';
        console.log('隐藏');
    } else if (document.visibilityState == "visible") {
        document.title = '欢迎回来';
        console.log('显示');
        setTimeout(() => {
            document.title='红提柚子的博客'
        }, 1000);
    }
});
<!-- 修改网站标题 -->